During a town hall event last night, House Speaker Paul Ryan was asked about illegal immigration, and he seemed to deviate from President-elect Donald Trump's platform.

Ryan agreed with Trump that sanctuary cities violate the law and they should not receive federal assistance.

As for the deportation of illegal immigrants, however, Ryan said, "It’s not happening."

Katrina Pierson, former spokesperson for Trump, and immigration attorney Francisco Hernandez discussed Ryan's comments on "The O'Reilly Factor" tonight, and things got pretty heated.

Pierson and Hernandez agreed that when Trump takes office, he alone will decide what to do about President Obama's executive order that offered protections and work permits to illegal immigrants, but they clashed on the legality - or mere existence - of sanctuary cities.

"There is no such thing as a 'sanctuary city,'" Hernandez said, arguing that there is no mandate that cities must comply with federal immigration law.

"Why do you need a law to tell law enforcement to enforce the law?" Pierson fired back. "There are sanctuary cities. The legislation is titled 'sanctuary cities,' and there are too many of them in this country."

She explained that sanctuary cities act as a "magnet" for illegal immigrants, including those who have already been deported, which is a huge problem.

"The only reason they come back is because they know they're safe in those cities. And that's when Americans get hurt."

Watch more above, and let us know what you think in the comments.

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